Livestock Science 144 (2012) 1–10

Contents lists available at SciVerse ScienceDirect

Livestock Science

j ourna l homepage: www.e lsev ie r .com/ locate / l ivsc i

Goat kids' intestinal absorptive mucosa in period of passiveimmunity acquisition

Débora Botéquio Moretti, Wiolene Montanari Nordi, Anali Linhares Lima, Patrícia Pauletti,Ivanete Susin, Raul Machado-Neto ⁎Department of Animal Science, University of São Paulo, Avenue, Pádua Dias 11, Piracicaba, São Paulo, Brazil

a r t i c l e i n f o

⁎ Corresponding author at: Avenue Pádua Dias, 11, 1São Paulo, Brazil. Tel.: +55 19 3429 4260; fax: +55 1

E-mail address: raul.machado@esalq.usp.br (R. Ma

1871-1413 © 2011 Elsevier B.V.doi:10.1016/j.livsci.2011.10.007

Open access under the E

a b s t r a c t

Article history:Received 6 July 2011Received in revised form 5 September 2011Accepted 11 October 2011

Colostrum intake in newborn goat kids is essential for the acquisition of immunoglobulins (Ig)and influencing development of gastrointestinal mucosa. The present study investigated smallintestine structure in the postnatal goat kid fed lyophilized bovine colostrum, an alternativesource of antibodies to small ruminants, or goat colostrum using scanning electron microscopytechnique. At 0, 7 and 14 h of life 15 male newborns received 5% of body weight of lyophilizedbovine colostrum (LBC) and 14 goat colostrum (GC), both with 55 mg/mL of IgG. Samples ofduodenum, medium jejunum and ileumwere collected at 18, 36 and 96 h of life. Three animalswere sampled at birth without colostrum intake (0 h). The enteric tissues were analyzed forvilli density (villi/cm2) and morphological characteristics. The villi density did not differ be-tween treatment, sampling time and intestinal segments (P>0.05). The morphological charac-teristics were not different between LBC and GC in all segments. Duodenal villi were fingerlike,thick and short, and with different heights. Duodenal folds could also be verified. Frequentanastomoses in all sampling times were observed in this segment. In the jejunum, fingerlikevilli, thin and thick, of different heights were observed in all sampling times as well as leaf-shaped villi. Vacuoles with colostrum were observed in the jejunum of goats sampled at18 h of life. In ileum, fingerlike villi were observed in all sampling times. At 0 and 96 h oflife, thick and low villi were verified while at 18 and 36 h the villi showed different heightsand widths. At all sampling times, regularly cell extrusion processes were observed withgrouped cells at the apex of the ileum villi and with isolated cells along the villi. In the first4 days of goat kids' life the small intestine structure was unaffected by different sources of co-lostrum, goat or lyophilized bovine, and by the replacement of fetal enterocytes, which are ableto absorb macromolecules, by adult-type ones.

© 2011 Elsevier B.V. Open access under the Elsevier OA license.

Keywords:DevelopmentIntestinal villiEnterocytesColostrumScanning electron microscopy

1. Introduction

In the first hours of life, major changes occur in the intesti-nal tract, especially in those of ruminants, and the alterationswill have important implications in the animals' development

3418-900, Piracicaba,9 3429 4883.chado-Neto).

lsevier OA license.

(Fleige et al., 2007; Kelly and Coutts, 2000; Masanetz et al.,2010). Besides the substitution of fetal-type enterocytes, whichhave the capacity to absorbmacromolecules, the small intestinalmucosa undergoes structural changes (Bessi et al., 2002a,b;Boudry et al., 2008; Campbell et al., 1977; Kelly and Coutts,2000; Skrzypek et al., 2005; Smeaton and Simpson-Morgan,1985).

Colostrum, a milk secretion responsible for providing an-tibodies to newborns, also has other components that are as-sociated with the development of the gastrointestinal tract,including the presence of high concentration of insulin-like

Table 1Chemical composition and IGF-I concentration of lyophilized bovine andgoat colostrum fed to newborn goat kids.

Lyophilized bovinecolostrum

Goatcolostrum

Humidity and volatility, % 81.11±0.19 79.88±0.18Dry matter, % 18.89±0.19 20.12±0.18Crude protein, % 9.40±0.07 9.77±0.06Fat, % 3.97±0.13 7.76±0.12IGF-I (ng/mL) 158.71±23.04 356.32±0.97

2 D.B. Moretti et al. / Livestock Science 144 (2012) 1–10

growth factor type I (Georgieva et al., 2003; Hammon andBlum, 2002; Odle et al., 1996). The deprivation of this milksecretion in the first hours of life can result in considerablemodifications in the small intestine, such as decrease of intes-tinal size (Kelly and Coutts, 2000).

In situations with the possibility of Caprine Arthritis En-cephalitis (CAE) Virus transmission, provision of colostrum tothe newborn goat kid is not recommended, so it is necessaryto search for an alternative management of colostrum (Castroet al., 2005; Lima et al., 2009; Logan et al., 1978; Quigley Iii etal., 2002). Bovine colostrum can provide antibodies to thesmall ruminants and is also an alternative that is easy to obtainand has high immune quality (Lima et al., 2009; Moretti et al.,2010a,b). Lyophilized colostrum is another alternative man-agement that allows storage for prolonged periods, thus ensur-ing the biological function and quantity of antibodies (Castro etal., 2005; Quigley Iii et al., 2002).

Morphological characteristics of goat kid enteric tissuewere investigated in newborns fed lyophilized bovine colos-trum, as an alternative source of antibodies, and goat colos-trum during the period of passive immunity acquisition.

2. Materials and methods

The experiment was conducted on the Intensive Systemof Sheep and Goats Production (ESALQ/USP). In this study,32 Saanen×Boer goat kids were available. The animals werekept, maintained and treated in adherence to accepted stan-dards for humane treatment of animals (authorized by ESALQ/USP ethics committee).

Bovine and goat 1st milking colostrum from two Holsteinscows and 14 Sannen×Boer goats were collected before the ex-periment. The colostrums were homogenized to form a uniquepool of bovine colostrumand another of goat colostrum. There-after the milking secretions were stored at−20 °C. Samples ofeach pool were collected for determination of IgG concentra-tion by radial immunodiffusion (Besser et al., 1985; Manciniet al., 1965). The frozen pool of bovine colostrum was con-ducted to the lyophilization process. The resulting powderwas homogenized and stored in a tightly sealed container at−20 °C.

At the time of offering the meals, the pool of goat colos-trum was diluted with whole milk until reaching a concen-tration of 55 mg/mL of IgG. The pool of bovine colostrumpowder, however, was resuspended in water until it reachedthe original chemical composition of the pool taken to the ly-ophilization process and, subsequently, diluted with wholemilk until reaching a concentration of 55 mg/mL of IgG. Sam-ples of final meals were collected for analysis of chemicalcomposition and IGF-I concentration (Table 1).

The newborn goat kids were separated from their mothersimmediately after birth, without maternal colostrum intake.Fifteen animals received 5% of body weight of lyophilized bo-vine colostrum (LBC group) and fourteen goat colostrum (GCgroup) as soon as possible after birth and at 7 and 14 h of life.Goat kids were randomly slaughtered at 18, 36 and 96 h forthe collection of duodenum, medium jejunum and ileum.Three other animals were sampled immediately after birthwithout colostrum ingestion constituting an additional group(0 h).

The small intestine segments were opened, the mucosaflushed with saline solution, and the samples were fixed in4% phosphate buffer paraformaldehyde solution overnightand, thereafter, in cacodylate-buffered Karnovsky's fixative.After post-fixation in OsO4 for 2 h, intestine sections werewashed with cacodylate buffered 0.1 M and dehydratedwith acetone (30, 50, 70, 90 and 100%, 10 min each concen-tration; 15 min at 100%). A critical-point drying apparatus(Balzers CPD-0302) was used to dry all tissue sections.

Processed tissues were fixed with adhesive to aluminumstubs and the sections were coated with 40 nm of gold inBalzers MED-0102 sputter coater. The samples were examinedwith a scanning electronic microscope Zeiss DSM-940A3, at50 kV. Ten images of each intestinal segment were collectedfor the determination of villi density (villi/cm2) and for mor-phological analysis.

2.1. Statistical analyses

A completely randomized design was used. The statisticalanalysis was performed using SAS software (SAS InstituteInc., 2008). The villi density in each segment was arrangedin a 2×3 factorial scheme. Treatment and sampling timewere considered to be the main effect. The variable was sub-mitted to analysis of variance (F test at 5% probability) usinggeneral linear mixed models (MIXED procedure). The 0 h an-imals were analyzed as an additional group by orthogonalcontrasts using PRC GLM program and compared to the Ftest at 5% probability. The values are presented as meansand standard errors.

The values of villi density were also analyzed indepen-dently of the treatment given to animals, lyophilized bovineor goat colostrum, through the PROC MIXED procedure ofSAS software in a 4×3 factorial scheme, with the main effectssampling time (0, 18, 36 and 96 h) and intestinal segments(duodenum, jejunum and ileum).

3. Results

The values of villi density (means±standard errors) are pre-sented in Table 2. There was no effect of treatment, samplingtime and interaction between the parameters (P>0.05) in anyintestinal segment. The villi density did not differ among the in-testinal segments and sampling time (P>0.05).

There were nomorphological differences in the duodenalvilli in different treatments and sampling times. The villiwere fingerlike, thick and short, with different heights (Fig. 1).Duodenal folds could also be verified. The frequent presence ofanastomoses of two and three villi was observed in this intestinal

Table 2Villi density (villi/cm2) in each intestinal segment of goat kids (means±standard errors).

Probability

0 h 18 h 36 h 96 h General mean Treatment Sampling time Interactiona Additional groupb

DuodenumLBC 8797±1798 7354±1854 7531±1821 7894±1038 0.59 0.53 0.54 0.56GC 9256±1799 10,591±2010 6395±2353 8747±1188General mean 6927±700 9027±1271 8972±1372 6963±1507

JejunumLBC 6513±532 7049±550 8271±538 7278±307 0.23 0.55 0.17 0.43GC 8068±533 7893±532 7592±696 7851±341General mean 7003±274 7290±376 7471±382 7931±445

IleumLBC 7124±747 6393±772 7145±756 6887±432 0.31 0.84 0.84 0.52GC 7382±748 7533±747 7738±977 7551±478General mean 6567±627 7253±528 6963±536 7442±625

LBC — goat kids that received 5% of body weight of lyophilized bovine colostrum at 0, 7 and 14 h of life, GC — goat kids that received 5% of body weight of goatcolostrum at 0, 7 and 14 h of life.

a Interaction between treatment and sampling time.b Effect of additional group (group sampled at birth without colostrum intake) by orthogonal contrast, F test (Pb0.05).

3D.B. Moretti et al. / Livestock Science 144 (2012) 1–10

segment (Fig. 2). Villiwithdome shapewere found in one animalsampled at 0 h (Fig. 3). Mucin exocytosis by globet cells couldalso be detected.

Columnar enterocytes could be observed in the absorptiveepithelium of goat kids (Fig. 4).

The jejunum, like the duodenum segment, did not showdifferences in morphology of the villi in the different treat-ments and sampling times. Fingerlike villi both thin andthick and of different heights were observed (Fig. 5). Leaf-shaped villi could also be verified. The structure of the ab-sorptive mucosa was higher than the other intestinal seg-ments. Anastomoses were not observed in this intestinalsegment. The brush border of enterocytes was well devel-oped, with microvilli that delimit the border of the cells,and globet cells were evident along the villi. Vacuoles of ab-sorption were verified in the jejunum of goat kids sampledat 18 h of life (Figs. 6 and 7). Fig. 8 suggests the presence ofcells, probably in the process of cell death, with holes intheir membranes and without microvilli. After cell loss, a re-gion of extrusion can be observed.

In the ileum, treatments did not affect morphologicalcharacteristics of the villi. Fingerlike villi were observed in

A

Fig. 1. (A) Fingerlike villi, thick and short, with different heights in the duodenum o

all sampling times. At 0 and 96 h of life, thick and low villiwere verified while at 18 and 36 h, the villi showed differentheights and widths (Fig. 9). Anastomoses were observed inthis intestinal segment, but with less frequency comparedto the duodenum. The frequent presence of grooves wasalso found in some animals, which led to a rocky shape tovilli (Fig. 10).

In the ileum, frequent cell extrusion processes, at all sam-pling times, were observed at the apex and along the villi(Fig. 11). When the cell loss was observed at the apex ofthe villi, it was often with a group of cells, while along thevilli, the death of isolated cells was observed.

Projections of Peyer's patches, lymph nodes present in theileum segment, were observed among the villi of all animals(Fig. 12).

4. Discussion

Colostrum is an important source of hormones and bioactivefactors that have activities associated with the maturation anddevelopment of the gastrointestinal tract (Blum and Hammon,2000; Morise et al., 2008; Odle et al., 1996; Pauletti et al.,

B

f goat kids; (B) Duodenal folds in the duodenum of goat kids; Bar=100 μm.

Fig. 2. Anastomoses between duodenal villi of goat kids; Bar=100 μm.

4 D.B. Moretti et al. / Livestock Science 144 (2012) 1–10

2007). Among the hormones and bioactive factors present inthis lacteal secretion, the insulin-like growth factor type I(IGF-I) is one of the most investigated (Blum and Baumrucker,2002; Buhler et al., 1998; Georgieva et al., 2003; Kelly andCoutts, 2000; Odle et al., 1996; Playford et al., 2000; Zhang etal., 1997). According to Kindlein (2006), the amount of IGF-Iprovided may influence villi density. The authors observedthat the ingestion of this bioactive factor less than500 μg deter-mined 25% of decrease in the ileal villi density of calves. In thepresent work, the amount of IGF-I ingested by the animals thatreceived lyophilized bovine and goat colostrum was very low,

A B

C D

Fig. 3. (A) and (B) Villi with dome morphology found in one animal at 0 h of life; Bar=40 μm; (C) and (D) Mucin exocitosis by globet cells in the duodenal villiBar=10 μm.

approximately 91 and 197 μg, respectively, which may be re-sponsible for the absence of differences in the villi densityin different treatments, sampling times and intestinal seg-ments. It is known, however, that the absorptive capacitydepends not only on villi density. The height of the villiand the microvilli also has a significant influence (Macari,1995, 1999). Therefore, the morphology of intestinal villiis also an important feature to be investigated in the intestinalepithelium.

In this study, there were no morphological differencesbetween treatments in all segments studied. In the duodenum,

;

Fig. 4. Columnar enterocytes in the absorptive epithelium of goat kids' small intestine; Bar=40 μm.

5D.B. Moretti et al. / Livestock Science 144 (2012) 1–10

the intestinal epithelium did not change villi shape in the firsthours of goat kids' life. Bessi et al. (2002b) and Kindlein et al.(2008), in turn, observed morphological differences betweenthe duodenum villi of newborn calves and animals 24-hoursold and 3-days old, respectively. The presence of intestinalanastomoses in this segment is in agreement with resultsfound by Bessi et al. (2002b) and Kindlein et al. (2008) in calvesand by Skrzypek et al. (2005) in pigs. However, the frequencyof these structures in the goat kids was higher than thatfound in cattle and pigs, whichmay have determined the pres-ence of duodenal folds.

A

DC

Fig. 5. (A), (B) and (C) Fingerlike villi thin and thick and with different heights obserof goat kids; Bar=100 μm.

In the jejunum, the villi were high and finger-like in ac-cordance with the literature (Bessi et al., 2002a,b; Kindleinet al., 2008; Poole et al., 2003). Villi in leaf form, such asthose observed in this study, were also detected by Kindleinet al. (2008) in 3-day-old calves. The tall villi present in thejejunum, as seen in the goat kids, are related to an increasein surface area and consequently with the highest conditionof absorption in this portion of the small intestine (Poole et al.,2003). In ruminants, this segment has significant importance tothe newborn animals, since the absorption of immunoglobulinsin the first hours of life occurs primarily in cells of jejunum and

B

ved in the jejunum of goat kids; (D) Leaf shaped villi observed in the jejunum

m

m

Fig. 6. Jejunum of goat kids sampled at 18 h of life showing vacuoles of colostrum absorption; Arrow: vacuoles of colostrum absorption; m: microvilli; Bar=5 μm

n

Fig. 7. Enterocytes with vacuoles of colostrum absorption in goat kids sampled at 18 h of life; Arrow: vacuoles of colostrum absorption; n: nucleus of the enter-ocytes; Bar=10 μm.

6 D.B. Moretti et al. / Livestock Science 144 (2012) 1–10

.

Fig. 8. Process of cell death and extrusion in the jejunum villi of goat kids; Bar=10 μm.

7D.B. Moretti et al. / Livestock Science 144 (2012) 1–10

ileum, while duodenum cells have negligible contribution in thisprocess (Trahair and Robinson, 1989). In this study, vacuoles ofabsorption containing colostrumwere verified in jejunumenter-ocytes of goat kids sampled at 18 h of life, a period of intense ac-tivity of macromolecule internalization. These vacuoles areabsorbed by pinocytosis and can appear in the bloodstream ofthe newborn within one to three hours after its ingestion(Castro et al., 2009; Lima et al., 2009; Moretti et al., 2010b;Pauletti et al., 2007). However, after 24 to 36 h, themembranesof enterocytes are altered and lose their ability to absorb macro-molecules, resulting in intestinal closure (Bessi et al., 2002a;

A B

Fig. 9. (A) Thick and low villi observed at 0 and 96 h of goat kids' life; (B) DifferenBar=100 μm.

Campbell et al., 1977; Smeaton and Simpson-Morgan, 1985).Probably because of the decrease of macromolecule internaliza-tion, vacuoles of absorption could not be observed by scanningelectron microscopy at 36 and 96 h of life.

In this study, there were changes in the morphology of theileal epithelium of goat kids at 18 and 36 h of life and, more-over, this was the segment that showed a higher frequency ofcells undergoing cell death. These characteristics indicatethat this region of the small intestine is greatly affected by co-lostrum ingestion. It is known that as epithelial cells areheading to the top of the villi, they undergo apoptosis and

t heights and widths of ileal villi observed at 18 and 36 h of goat kids' life;

Fig. 10. Grooves in the ileal segment of goat kids leading to a rocky aspect of the villi; Bar=100 μm.

8 D.B. Moretti et al. / Livestock Science 144 (2012) 1–10

extrusion into the intestinal lumen. However, this studyshows that cell loss may also occur along the villi, indicatingthat other components that arrive in this segment can beharmful to intestinal cells and, consequently, stimulatesearly death.

The absence of morphological differences in the villi of goatkids suckled lyophilized bovine or goat colostrum indicates

Fig. 11. Cellular extrusion process occurring at the apex of the villi with a group of cells and empty spaces corresponding to isolated dead cells; Bar=40 μm.

that the source of heterologous antibodies does not cause injuryon the development of the intestinal epithelium of these smallruminants. Thus, the present work ensures this source of Ig as apossible substitute for goat colostrum.

In the first 4 days of goat kids' life the small intestine struc-ture was unaffected by different sources of colostrum, goat orlyophilized bovine, and by the replacement of fetal enterocytes,

Fig. 12. Projections of Peyer's patches observed among the ileal villi of goat kids; Bar=10 μm.

9D.B. Moretti et al. / Livestock Science 144 (2012) 1–10

which are able to absorb macromolecules, by adult-type ones.

Acknowledgments

We gratefully acknowledge FAPESP for the funding toconduct this experiment. We also thank the Núcleo deApoio à Pesquisa/Microscopia Eletrônica aplicada à PesquisaAgrícola (NAP/MEPA - ESALQ-USP) for the Scanning EletronicMicroscope.

References

Besser, T.E., Garmedia, A.E., McGuire, T.C., Gay, C.C., 1985. Effect of colostralimmunoglobulin G1 and immunoglobulin M concentrations on immu-noglobulin absorption in calves. J. Dairy Sci. 68, 2033–2037.

Bessi, R., Pauletti, P., d'Arce, R.D., Neto, R.M., 2002a. Colostral antibodies ab-sorption in calves. II. Distal small intestine study. Rev. Bras. Zootecn.Braz. J. Anim. Sci. 31, 2325–2331.

Bessi, R., Pauletti, P., d'Arce, R.D., Neto, R.M., 2002b. Colostral antibodies absorp-tion in dairy calves. I. Proximal small intestine study. Rev. Bras. Zootecn.Braz. J. Anim. Sci. 31, 2314–2324.

Blum, J.W., Baumrucker, C.R., 2002. Colostral and milk insulin-likegrowth factors and related substances: mammary gland and neona-tal (intestinal and systemic) targets. Domest. Anim. Endocrinol. 23,101–110.

Blum, J.W., Hammon, H., 2000. Colostrum effects on the gastrointestinaltract, and on nutritional, endocrine and metabolic parameters in neona-tal calves. Livest. Prod. Sci. 66, 151–159.

Boudry, C., Dehoux, J.-P., Wavreille, J., Portetelle, D., Théwis, A., Buldgen, A.,2008. Effect of a bovine colostrum whey supplementation on growthperformance, faecal Escherichia coli population and systemic immune re-sponse of piglets at weaning. Animal 2, 730–737.

Buhler, C., Hammon, H., Rossi, G.L., Blum, J.W., 1998. Small intestinal mor-phology in eight-day-old calves fed colostrum for different durationsor only milk replacer and treated with long-R-3-insulin-like growth fac-tor I and growth hormone. J. Anim. Sci. 76, 758–765.

Campbell, S.G., Siegel, M.J., Knowlton, B.J., 1977. Sheep immunoglobulins andtheir transmission to neonatal lamb. N. Z. Vet. J. 25, 361–365.

Castro, N., Capote, J., Álvarez, S., Argüello*, A., 2005. Effects of lyophilizedcolostrum and different colostrum feeding regimens on passivetransfer of immunoglobulin G in Majorera goat kids. J. Dairy Sci. 88,3650–3654.

Castro, N., Capote, J., Morales-delaNuez, A., Rodríguez, C., Argüello, A., 2009.Effects of newborn characteristics and length of colostrum feeding peri-od on passive immune transfer in goat kids. J. Dairy Sci. 92, 1616–1619.

Fleige, S., Preißinger, W., Meyer, H.H.D., Pfaffl, M.W., 2007. Effect of lactuloseon growth performance and intestinal morphology of pre-ruminant

calves using a milk replacer containing Enterococcus faecium. Animal 1,367–373.

Georgieva, T.M., Georgiev, I.P., Ontsouka, E., Hammon, H.M., Pfaffl, M.W.,Blum, J.W., 2003. Abundance of message for insulin-like growthfactors-I and -II and for receptors for growth hormone, insulin-likegrowth factors-I and -II, and insulin in the intestine and liver of pre-and full-term calves. J. Anim. Sci. 81, 2294–2300.

Hammon, H.M., Blum, J.W., 2002. Feeding different amounts of colostrum oronly milk replacer modify receptors of intestinal insulin-like growth fac-tors and insulin in neonatal calves. Domest. Anim. Endocrinol. 22,155–168.

Kelly, D., Coutts, A.G.P., 2000. Development of digestive and immunologicalfunction in neonates: role of early nutrition. Livest. Prod. Sci. 66,161–167.

Kindlein, L., 2006. Efeito de IgG e IGF-I das primeiras refeições lácteas sobre aflutuação sérica e características do epitélio intestinal em bezerrosrecém-nascidos. 2006. 101p. PhD thesis - Escola Superior de Agricultura“Luiz de Queiroz”, Universidade de São Paulo, Piracicaba.

Kindlein, L., Pauletti, P., Bagaldo, A.R., Rodrigues, A.P.O., Machado-Neto, R.,2008. Effects of enriched colostrum supply in intestinal mucosa mor-phology of newborn calves. Acta Sci. Vet. 36, 31–34.

Lima, A.L., Pauletti, P., Susin, I., Machado-Neto, R., 2009. Fluctuation of serumvariables in goats and comparative study of antibody absorption in new-born kids using cattle and goat colostrum. Rev. Bras. Zootecn. Braz. J.Anim. Sci. 38, 2211–2217.

Logan, E.F., Foster, W.H., Irwin, D., 1978. A note on bovine colostrum as analternative source of immunoglobulin for lambs. Anim. Sci. 26,93–96.

Macari, M., 1995. Mecanismos de proliferação e reparação da mucosa gas-trintestinal em aves, in: Simpósio de cocciodiose e enterite (Anais).CBNA, Campinas. p. 29–48.

Macari, M., 1999. Fisiologia do sistema digestivo das aves (I). Aves e Ovos,Campinas, n.8/9, p. 12–20.

Mancini, G., Carbonara, A.O., Heremans, J.F., 1965. Immunochemical quantita-tion of antigens by single radial immunodiffusion. Immunochemistry 2,235–254.

Masanetz, S., Wimmer, N., Plitzner, C., Limbeck, E., Preißinger, W., Pfaffl,M.W., 2010. Effects of inulin and lactulose on the intestinal morphologyof calves. Animal 4, 739–744.

Moretti, D.B., Kindlein, L., Pauletti, P., Machado-Neto, R., 2010a. IgG absorp-tion by Santa Ines lambs fed Holstein bovine colostrum or Santa Inesovine colostrum. Animal 4, 933–937.

Moretti, D.B., Pauletti, P., Kindlein, L., Machado-Neto, R., 2010b. Enteric cellproliferation in newborn lambs fed bovine and ovine colostrum. Livest.Sci. 127, 262–266.

Morise, A., Louveau, I., Le Huërou-Luron, I., 2008. Growth and develop-ment of adipose tissue and gut and related endocrine status duringearly growth in the pig: impact of low birth weight. Animal 2,73–83.

Odle, J., Zijlstra, R.T., Donovan, S.M., 1996. Intestinal effects of milkbornegrowth factors in neonates of agricultural importance. J. Anim. Sci. 74,2509–2522.

10 D.B. Moretti et al. / Livestock Science 144 (2012) 1–10

Pauletti, P., Bagaldo, A.R., Kindlein, L., Machado, R., 2007. Insulin-likegrowth factor-I, passive immunity transfer, and stereological charac-teristics of small intestine of newborn calves. Anim. Sci. J. 78,631–638.

Playford, R.J., Macdonald, C.E., Johnson,W.S., 2000. Colostrumandmilk-derivedpeptide growth factors for the treatment of gastrointestinal disorders. Am.J. Clin. Nutr. 72, 5–14.

Poole, C.A.,Wong, E.A.,McElroy, A.P., Veit, H.P.,Webb, K.E., 2003. Ontogenesis ofpeptide transport and morphological changes in the ovine gastrointestinaltract. Small Ruminant Res. 50, 163–176.

Quigley Iii, J.D., Kost, C.J., Wolfe, T.M., 2002. Absorption of protein and IgG incalves fed a colostrum supplement or replacer. J. Dairy Sci. 85, 1243–1248.

SAS Institute Inc., 2008. SAS/STAT ® 9.2 User’s Guide. Cary, NC: SAS InstituteInc.

Skrzypek, T., Valverde Piedra, J.L., Skrzypek, H., Wolinski, J., Kazimierczak,W., Szymanczyk, S., Pawlowska, M., Zabielski, R., 2005. Light and scanningelectron microscopy evaluation of the postnatal small intestinal mucosadevelopment in pigs. J. Physiol. Pharmacol. 56 (Suppl 3), 71–87.

Smeaton, T.C., Simpson-Morgan, M.W., 1985. Epithelial cell renewal andantibody transfer in the intestine of the foetal and neonatal lamb. Aust.J. Exp. Biol. Med. 63, 41–51.

Trahair, J.F., Robinson, P.M., 1989. Enterocyte ultrastructure and uptake ofimmunoglobulins in the small-intestine of the neonatal lamb. J. Anat.166, 103–111.

Zhang, H.Z., Malo, C., Buddington, R.K., 1997. Suckling induces rapid intestinalgrowth and changes in brush border digestive functions of newborn pigs.J. Nutr. 127, 418–426.